Corneal contact lens

ABSTRACT

A corneal contact lens having a transparent central zone is provided with an irregular pattern of colored striations in the surrounding peripheral zone in order to highlight the natural color of the wearer&#39;&#39;s iris, without requiring a lens large enough to cover the entire iris. Transparent regions about the striations extend the optical area into the peripheral zone so that central vision is not restricted and peripheral vision is improved.

nited States Patent 'LeGrand et al. 1 51 Jan. 23, 1973 CORNEAL CONTACTLENS FOREIGN PATENTS OR APPLICATIONS [76] lnventors: Joseph A. LeGrand,16 Arrowhead 1,115,140 12/1955 France ..351/100 Trail, Media, Pa. 19063;Arl Fuhrman, 6624 Rutland Street, phlladel- OTHER PUBLICATIONS P Pa.19306 Soehnges, Article in Contacto Vol. 12 No. 1 March, 22 Filed: 061.23, 1970 [21] Appl. No.: 83,453 Primary ExaminerDavid H. RubinAttorney-Edward A. Sager [52] US. Cl ..351/160, 351/162 [57] ABSTRACT[51] Int. Cl. ..G02c 7/04 58 Field of Search ..35l/160, 162-, 43/1, 13 Alens a anspaem central zone is provided with an irregular pattern ofcolored striations in the surrounding peripheral zone in order [56]References Cited to highlight the natural color of the wearers iris,

UNITED STATES PATENTS without requiring a lens large enough to cover theentire iris. Transparent regions about the striations ex- 3t454v3327/1969 Slegelm tend the optical area into the peripheral zone so that2,593,150 4/1952 Jal'don x central vision is not restricted andperipheral vision is 2,673,369 3/1954 Galeski ..351/16O x improved3,034,403 5/1962 Neefe ..35l/l62 3,536,386 10/1970 Spivack ..351/160 7Claims, 5 Drawing Figures PATENTEU M I 3.712.718

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INVEYTORS JOSFPH a, Le GRA ND ARI fL/HRMAN CORNEAL CONTACT LENS Thisinvention relates to corneal contact lenses of plastic material, andmore particularly to those of the type adapted for cosmetic use as wellas for correction of vision.

Fully transparent contact lenses intended only for correction of visionmay be made with a lens diameter of 8 to I millimeters in order to covera dilated pupil. However, conventional cosmetic lenses retained on thecornea have been made larger, usually in the range of 10.5 to 12millimeters, in order to provide a colored peripheral zone or irisportion which fully covers the wearers iris. The greater size and weightof conventional cosmetic lenses is disadvantageous.

Cosmetic contact lenses also require a central optical zone or pupilportion of about 4 to millimeters in diameter which is made transparentfor visual transmission. This central zone provides optical correctionwhen the outer surface of the lens is ground and polished to prescribedcurvature, taking into account the curvature of the inner surface of thelens which is fitted to the wearers cornea. With a circular central zoneof fixed diameter found on conventional lenses of this type, as well asthe peripheral colored area of low light transmissivity, the wearerexperiences some visual obscurity when his pupils dilate to accommodatefor reduced illumination.

The present invention is directed to overcoming the aforementioneddisadvantages of conventional lenses and to gaining a number ofadvantages thereover.

According to the present invention, a corneal contact lens, 8 to I0millimeters in diameter and having a transparent central zone, isprovided with an irregular pattern of colored striations in thesurrounding peripheral zone. Transparent regions about the striationsextend the optical zone to provide a wider visual field than isobtainable with lenses having a fully colored peripheral zone. Thestriations extend for the full thickness of the lens, and therefore thestriations will appear in the lens after final grinding as they do inthe lens blank, without retouching or further processing to obtain thedesired cosmetic result.

The striations serve to accentuate or highlight the wearers iris ratherthan to cover it completely with an entirely new color. This approachobtains a desirable cosmetic advantage with a lens of small diameter, sothat the disadvantage of increased size and weight is avoided.

A lens made according to the invention is free of laminations and voids.The striations providing color are surrounded by transparent regionswhich together with the transparent central zone consist of a Singlehomogeneous phase of acrylic polymer material bonded to the materialcomprising the striations. The resultant lens is a unitary body havingstructural integrity which is rugged and dependable, and which lendsitself to convenient manufacture.

In the drawings:

FIG. 1 is a plan view of a lens blank, showing the concave side thereof;

FIG. 2 is a transverse sectional view of the blank of FIG..1, taken onthe line 2 2 thereof, with the concave side facing downwardly;

FIG. 3 is a plan view of a corneal contact lens made according to theinvention and showing the convex side thereof;

FIG. 4 is a transverse sectional of the corneal contact lens of FIG. 3,taken on the line 4 4 of FIG. 3; and

FIG. 5 is a view similar to FIG. 3, but showing a modified form ofcorneal contact lens made according to the invention.

Referring to the drawings in greater detail, the finished lens 14 ofFIGS. 3 and 4 or FIG. 5 is made by removal of material from the blank orbutton 12 of FIGS. 1 and 2.

The finished lens 14 is concavo-convex in cross section, appearing as acircular segment of a thin-walled hollow sphere. The lens 14 has acontinuously convex outer face 16, the surface of which may be formedabout an imaginary point and at a constant radius therefrom. Inaddition, the lens 14 has a continuously concave inner face 18, thesurface of which may also be formed with all portions at like radialdistances from an imaginary point. The last-mentioned imaginary pointmay be some distance from the other imaginary point. The outer face 16and the inner face 18 are separated by the thickness of the lens 14.

The lens 14 described herein is made from plastic material of opticalquality; and although the invention is not so limited polymethylmethacrylate or any other suitable acrylic polymer material ispreferred. The button 12 is a single homogeneous phase of such material,preferably 7% inch in diameter and 3/16 inch' thick, before any cuts oradditions are made thereon.

As shown in FIG. 3, the lens 14 has an outside diameter which isapproximately in the range of between 8 and 10 millimeters,substantially the same as is preferred for corneal contact lenses whichare not used for cosmetic purposes and are entirely clear. The lens 14has a clear or transparent central zone 20 covering an area having adiameter from 4 to 5 millimeters. The central zone 20 is centered withinan annular peripheral zone 22 bounded on the outside by the edge 24 ofthe lens and on the inside by the central zone. A distinct borderbetween the zones 20 and 22 does not appear in the lens 14 of FIG. 3 asit does in the lens of FIG. 5. When worn, the central zone 20 covers thewearers pupil and the peripheral zone 22 overlies the wearers iris orportion thereof; and therefore the central zone 20 is an optical zonethrough which visual transmissions are made to the eye, while theperipheral zone 22 contains the colored matter used to gain a cosmeticadvantage.

The peripheral zone 22 comprises an annular array of colored striations26 and transparent regions 28, the striations being of substantiallyuniform composition for the thickness of the lens. The striations 26have substantially less light transmissivity than the central zone 20and the transparent regions 28. As best seen in FIG. 3, the, striations26 are linear and curvilinear stripes extending in generally radialdirection, some appearing like arrowheads, mostly in groups of severalof them which contact one another and converge in the direction of thecentral zone 20. The inner and outer ends of the radially extendingstriations 26 define an irregular pattern.

The transparent regions 28 of the peripheral zone 22 are disposedbetween at least portions of neighboring striations 26, and also betweenat least portions of the striations and the edge 24 of the lens 14. Inthe case of the lens 14 shown in FIG. 3 the transparent regions 28 arecontiguous to the transparent central zone 20, thus providing an outerextension of the central zone which widens the wearers field of visionand makes him unaware of the striations 26 adjacent the optical zone ofthe lens. This is an advantage over cosmetic lenses having peripheralzones which restrict the field of vision, as with opaque or nearlyopaque coloring material over this entire portion of the lens.

For applications where a more distinct peripheral zone 22 is required orpreferred, the lens 14 of FIG. 5 may be employed. It is characterized bya circular striation 30 which is formed about the central zone and isadjacent thereto. The circular striation connects the groups ofstriations 26 at the ends thereof near the central zone 20. Althoughthis form of the invention does not have transparent regions 28contiguous to the central zone 20, it does have such regions 28 in theperipheral zone 22.

Whether the lens of FIG. 5 or FIG. 3 is employed for cosmetic reasons,it is a feature of the present invention that the transparent regions 28permit the wearers iris to be the base color while the striations 26provide highlighting or contrasting color. Yet this is accomplished witha lens of small diameter.

The lens 14 is made by first cutting the inner face 18 to the desiredconcave shape in a piece of plastic material of the type described. Thenthe striations 26 are cut or formed in the concave face 18 in anysuitable manner to a depth of at least 0.15 millimeter, and the cuts arefilled. The filling material preferably comprises acrylic powder mixedwith a liquid containing an acrylic monomer, such as methylmethacrylate, which polymerizes with the aid of a catalyst in thepowder, and also translucent coloring matter. The latter is preferably anatural or earth pigment, although any stable, non-toxic, non-irritatingmaterial may be considered for use as coloring matter. For a furtherdiscussion of materials in general use for making contact lenses of thistype, reference is made to U.S. Pat. No. 3,454,332 which was grantedJuly 8, 1969 to Robert Siegel.

With the filling material in plastic condition it is packed into thecuts to fill them, and then the button 12 is heated to cure the fillingmaterial, preferably at 212 F. After curing the striation material willbe found bonded to the transparent material around it, thus forming anintegral, unitary body therewith. It is an advantage of the presentinvention that the lens blank I2 is made without laminations, and it isfree of objectionable voids by which the lens of U.S. Pat. No. 3,454,332is characterized in that specification and the appended claims. Bythorough mixing of the filling material and careful packing of the cuts,the striations 26 are of uniform composition for the thickness of thelens. Due to the presence of the coloring matter the striations havesubstantially less light transmissivity than the transparent regions 28and the central zone 20. If the coloring matter is a metallic orreflective pigment, the striations 26 highlight the wearer's iris in anunusual manner.

The lens 14 shown in FIG. 3 is made from the button 12 of FIGS. 1 and 2by cutting away the material above the concave surface 18 to a lensthickness of about 0. 1 5 millimeters, thereby forming the outer orconvex face 16 of the lens. Since the striations are made to at leastthis depth, they extend from one face to the other for the fullthickness of the finished lens 14. The edge 24 of the lens 14 is alsorounded to a very small radius. All surfaces are smoothly polished.

The finished lens 14 is ground and polished to provide the opticalcharacteristics prescribed for the wearer. This is usually done to theouter or convex face 16 only, providing a continuously convex face ofconstant radius. Although a plano lens is shown in FIG. 4, a finishedlens 14 most frequently possesses non-uniform thickness. It is to beappreciated that even with a lens of non-uniform thickness thestriations 26 provide uniform highlighting, since the striations extendfor the thickness of the lens. It is therefore possible to produce alens to the prescribed optical curvature and with coloration on theouter face 16 simultaneously with the final grinding and polishing stepsof the lens making process. There is no need for further attention by aspecialist in lens coloring after the lens is made to opticalspecifications.

It is especially advantageous that the lens 14 produces a highlysatisfactory cosmetic effect even though the lens is smaller than thewearer's iris. In addition, the lens of the present invention provides awider field of vision than has been possible heretofore with other knownlenses of this general type.

What is claimed is:

l. A corneal contact lens of generally concavo-convex cross section andhaving the approximate shape of a circular segment of a thin-walledhollow sphere, said lens having a continuously convex outer face and acontinuously concave inner face, said faces being separated by thethickness of the lens, said lens having an annular peripheral zonebounded by the edge of said lens and having a central zone substantiallycentered in said peripheral zone, the outside diameter of the annularperipheral zone being approximately in the range of between 8 and 10millimeters and the diameter of the central zone being approximately inthe range of between 4 and 5 millimeters, the central zone beingsubstantially transparent, the peripheral zone comprising an annulararray of colored striations and substantially transparent regions, saidtransparent regions being disposed in annular formation between at leastportions of neighboring striations and between at least portions of saidstriations and the edge of said lens; said central zone and saidtransparent regions consisting of a single homogeneous phase of materialof optical quality, said striations being of substantially uniformcomposition for the thickness of the lens and having lighttransmissivity substantially smaller than the light transmissivity ofsaid central zone and said transparent regions, said striations beingbonded to said central zone and said transparent regions and formingtherewith an integral, unitary body, whereby said transparent regionsextend the optical zone of said lens from said central zone to the edgeof said lens.

2. A corneal contact lens according to claim 1 wherein said materialconsists mainly of acrylic polymer material.

3. A corneal contact lens according to claim 2 wherein the compositionof said striations is essentially a mixture of acrylic polymer materialand translucent coloring matter.

wherein the ends of the striations closest to the central zone define anirregular pattern.

7. A corneal contact lens according to claim 5 wherein the striationsinclude a circular striation formed about, and adjacent to, said centralzone; said circular striation connecting the groups of striations at theends thereof closest to said central zone.

1. A corneal contact lens of generally concavo-convex cross section andhaving the approximate shape of a circular segment of a thin-walledhollow sphere, said lens having a continuously convex outer face and acontinuously concave inner face, said faces being separated by thethickness of the lens, said lens having an annular peripheral zonebounded by the edge of said lens and having a central zone substantiallycentered in said peripheral zone, the outside diameter of the annularperipheral zone being approximately in the range of between 8 and 10millimeters and the diameter of the central zone being approximately inthe range of between 4 and 5 millimeters, the central zone beingsubstantially transparent, the peripheral zone comprising an annulararray of colored striations and substantially transparent regions, saidtransparent regions being disposed in annular formation between at leastportions of neighboring striations and between at least portions of saidstriations and the edge of said lens; said central zone and saidtransparent regions consisting of a single homogeneous phase of materialof optical quality, said striations being of substantially uniformcomposition for the thickness of the lens and having lighttransmissivity substantially smaller than the light transmissivity ofsaid central zone and said transparent regions, said striations beingbonded to said central zone and said transparent regions and formingtherewith an integral, unitary body, whereby said transparent regionsextend the optical zone of said lens from said central zone to the edgeof said lens.
 2. A corneal contact lens according to claim 1 whereinsaid material consists mainly of acrylic polymer material.
 3. A cornealcontact lens according to claim 2 wherein the composition of saidstriations is essentially a mixture of acrylic polymer material andtranslucent coloring matter.
 4. A corneal contact lens according toclaim 1 wherein the striations are divided mostly into groups of severalof them which are in contact with one another and converge in thegeneral direction of said central zone.
 5. A corneal contact lensaccording to claim 4 wherein the ends of the striations closest to theedge of the lens define an irregular pattern.
 6. A corneal contact lensaccording to claim 5 wherein the ends of the striations closest to thecentral zone define an irregular pattern.
 7. A corneal contact lensaccording to claim 5 wherein the striations include a circular striationformed about, and adjacent to, said central zone; said circularstriation connecting the groups of striations at the ends thereofclosest to said central zone.